DBC/decoder.py
2020-10-12 15:39:25 -07:00

84 lines
2.4 KiB
Python

# Copyright (c) Facebook, Inc. and its affiliates.
# All rights reserved.
# This source code is licensed under the license found in the
# LICENSE file in the root directory of this source tree.
import torch
import torch.nn as nn
class PixelDecoder(nn.Module):
def __init__(self, obs_shape, feature_dim, num_layers=2, num_filters=32):
super().__init__()
self.num_layers = num_layers
self.num_filters = num_filters
self.init_height = 4
self.init_width = 25
num_out_channels = 3 # rgb
kernel = 3
self.fc = nn.Linear(
feature_dim, num_filters * self.init_height * self.init_width
)
self.deconvs = nn.ModuleList()
pads = [0, 1, 0]
for i in range(self.num_layers - 1):
output_padding = pads[i]
self.deconvs.append(
nn.ConvTranspose2d(num_filters, num_filters, kernel, stride=2, output_padding=output_padding)
)
self.deconvs.append(
nn.ConvTranspose2d(
num_filters, num_out_channels, kernel, stride=2, output_padding=1
)
)
self.outputs = dict()
def forward(self, h):
h = torch.relu(self.fc(h))
self.outputs['fc'] = h
deconv = h.view(-1, self.num_filters, self.init_height, self.init_width)
self.outputs['deconv1'] = deconv
for i in range(0, self.num_layers - 1):
deconv = torch.relu(self.deconvs[i](deconv))
self.outputs['deconv%s' % (i + 1)] = deconv
obs = self.deconvs[-1](deconv)
self.outputs['obs'] = obs
return obs
def log(self, L, step, log_freq):
if step % log_freq != 0:
return
for k, v in self.outputs.items():
L.log_histogram('train_decoder/%s_hist' % k, v, step)
if len(v.shape) > 2:
L.log_image('train_decoder/%s_i' % k, v[0], step)
for i in range(self.num_layers):
L.log_param(
'train_decoder/deconv%s' % (i + 1), self.deconvs[i], step
)
L.log_param('train_decoder/fc', self.fc, step)
_AVAILABLE_DECODERS = {'pixel': PixelDecoder}
def make_decoder(
decoder_type, obs_shape, feature_dim, num_layers, num_filters
):
assert decoder_type in _AVAILABLE_DECODERS
return _AVAILABLE_DECODERS[decoder_type](
obs_shape, feature_dim, num_layers, num_filters
)